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21 * @file cadet/gnunet-service-cadet_connection.c
22 * @brief GNUnet CADET service connection handling
23 * @author Bartlomiej Polot
26 #include "gnunet_util_lib.h"
27 #include "gnunet_statistics_service.h"
28 #include "cadet_path.h"
29 #include "cadet_protocol.h"
31 #include "gnunet-service-cadet_connection.h"
32 #include "gnunet-service-cadet_peer.h"
33 #include "gnunet-service-cadet_tunnel.h"
37 * Should we run somewhat expensive checks on our invariants?
39 #define CHECK_INVARIANTS 0
42 #define LOG(level, ...) GNUNET_log_from (level,"cadet-con",__VA_ARGS__)
43 #define LOG2(level, ...) GNUNET_log_from_nocheck(level,"cadet-con",__VA_ARGS__)
46 #define CADET_MAX_POLL_TIME GNUNET_TIME_relative_multiply (\
47 GNUNET_TIME_UNIT_MINUTES,\
52 /******************************************************************************/
53 /******************************** STRUCTS **********************************/
54 /******************************************************************************/
57 * Handle for messages queued but not yet sent.
59 struct CadetConnectionQueue
62 struct CadetConnectionQueue *next;
63 struct CadetConnectionQueue *prev;
66 * Peer queue handle, to cancel if necessary.
68 struct CadetPeerQueue *peer_q;
71 * Continuation to call once sent.
76 * Closure for @e cont.
81 * Was this a forced message? (Do not account for it)
88 * Struct to encapsulate all the Flow Control information to a peer to which
89 * we are directly connected (on a core level).
91 struct CadetFlowControl
94 * Connection this controls.
96 struct CadetConnection *c;
98 struct CadetConnectionQueue *q_head;
99 struct CadetConnectionQueue *q_tail;
102 * How many messages are in the queue on this connection.
104 unsigned int queue_n;
107 * How many messages do we accept in the queue.
108 * If 0, the connection is broken in this direction (next hop disconnected).
110 unsigned int queue_max;
113 * ID of the next packet to send.
118 * ID of the last packet sent towards the peer.
120 uint32_t last_pid_sent;
123 * ID of the last packet received from the peer.
125 uint32_t last_pid_recv;
128 * Bitmap of past 32 messages received:
129 * - LSB being @c last_pid_recv.
130 * - MSB being @c last_pid_recv - 31 (mod UINTMAX).
132 uint32_t recv_bitmap;
135 * Last ACK sent to the peer (peer can't send more than this PID).
137 uint32_t last_ack_sent;
140 * Last ACK sent towards the origin (for traffic towards leaf node).
142 uint32_t last_ack_recv;
145 * Task to poll the peer in case of a lost ACK causes stall.
147 struct GNUNET_SCHEDULER_Task *poll_task;
150 * How frequently to poll for ACKs.
152 struct GNUNET_TIME_Relative poll_time;
155 * Queued poll message, to cancel if not necessary anymore (got ACK).
157 struct CadetConnectionQueue *poll_msg;
160 * Queued poll message, to cancel if not necessary anymore (got ACK).
162 struct CadetConnectionQueue *ack_msg;
166 * Keep a record of the last messages sent on this connection.
168 struct CadetConnectionPerformance
171 * Circular buffer for storing measurements.
173 double usecsperbyte[AVG_MSGS];
176 * Running average of @c usecsperbyte.
181 * How many values of @c usecsperbyte are valid.
186 * Index of the next "free" position in @c usecsperbyte.
193 * Struct containing all information regarding a connection to a peer.
195 struct CadetConnection
198 * Tunnel this connection is part of.
200 struct CadetTunnel *t;
203 * Flow control information for traffic fwd.
205 struct CadetFlowControl fwd_fc;
208 * Flow control information for traffic bck.
210 struct CadetFlowControl bck_fc;
213 * Measure connection performance on the endpoint.
215 struct CadetConnectionPerformance *perf;
218 * ID of the connection.
220 struct GNUNET_CADET_Hash id;
223 * Path being used for the tunnel. At the origin of the connection
224 * it's a pointer to the destination's path pool, otherwise just a copy.
226 struct CadetPeerPath *path;
229 * Task to keep the used paths alive at the owner,
230 * time tunnel out on all the other peers.
232 struct GNUNET_SCHEDULER_Task *fwd_maintenance_task;
235 * Task to keep the used paths alive at the destination,
236 * time tunnel out on all the other peers.
238 struct GNUNET_SCHEDULER_Task *bck_maintenance_task;
241 * Queue handle for maintainance traffic. One handle for FWD and BCK since
242 * one peer never needs to maintain both directions (no loopback connections).
244 struct CadetPeerQueue *maintenance_q;
247 * Should equal #get_next_hop(), or NULL if that peer disconnected.
249 struct CadetPeer *next_peer;
252 * Should equal #get_prev_hop(), or NULL if that peer disconnected.
254 struct CadetPeer *prev_peer;
257 * State of the connection.
259 enum CadetConnectionState state;
262 * Position of the local peer in the path.
264 unsigned int own_pos;
267 * Pending message count.
269 unsigned int pending_messages;
273 * - if 0, connection in use.
274 * - if 1, destroy on last message.
275 * - if 2, connection is being destroyed don't re-enter.
280 * In-connection-map flag. Sometimes, when @e destroy is set but
281 * actual destruction is delayed to enable us to finish processing
282 * queues (i.e. in the direction that is still working), we remove
283 * the connection from the map to prevent it from still being
284 * found (and used) by accident. This flag is set to #GNUNET_YES
285 * for a connection that is not in the #connections map. Should
286 * only be #GNUNET_YES if #destroy is also non-zero.
291 * Counter to do exponential backoff when creating a connection (max 64).
293 unsigned short create_retry;
296 * Task to check if connection has duplicates.
298 struct GNUNET_SCHEDULER_Task *check_duplicates_task;
302 /******************************************************************************/
303 /******************************* GLOBALS ***********************************/
304 /******************************************************************************/
307 * Global handle to the statistics service.
309 extern struct GNUNET_STATISTICS_Handle *stats;
312 * Local peer own ID (memory efficient handle).
314 extern GNUNET_PEER_Id myid;
317 * Local peer own ID (full value).
319 extern struct GNUNET_PeerIdentity my_full_id;
322 * Connections known, indexed by cid (CadetConnection).
324 static struct GNUNET_CONTAINER_MultiHashMap *connections;
327 * How many connections are we willing to maintain.
328 * Local connections are always allowed,
329 * even if there are more connections than max.
331 static unsigned long long max_connections;
334 * How many messages *in total* are we willing to queue, divide by number of
335 * connections to get connection queue size.
337 static unsigned long long max_msgs_queue;
340 * How often to send path keepalives. Paths timeout after 4 missed.
342 static struct GNUNET_TIME_Relative refresh_connection_time;
345 * How often to send path create / ACKs.
347 static struct GNUNET_TIME_Relative create_connection_time;
350 /******************************************************************************/
351 /******************************** STATIC ***********************************/
352 /******************************************************************************/
356 #if 0 // avoid compiler warning for unused static function
358 fc_debug (struct CadetFlowControl *fc)
360 LOG (GNUNET_ERROR_TYPE_DEBUG, " IN: %u/%u\n",
361 fc->last_pid_recv, fc->last_ack_sent);
362 LOG (GNUNET_ERROR_TYPE_DEBUG, " OUT: %u/%u\n",
363 fc->last_pid_sent, fc->last_ack_recv);
364 LOG (GNUNET_ERROR_TYPE_DEBUG, " QUEUE: %u/%u\n",
365 fc->queue_n, fc->queue_max);
369 connection_debug (struct CadetConnection *c)
373 LOG (GNUNET_ERROR_TYPE_INFO, "DEBUG NULL CONNECTION\n");
376 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s:%X\n",
377 peer2s (c->t->peer), GCC_2s (c));
378 LOG (GNUNET_ERROR_TYPE_DEBUG, " state: %u, pending msgs: %u\n",
379 c->state, c->pending_messages);
380 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD FC\n");
381 fc_debug (&c->fwd_fc);
382 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK FC\n");
383 fc_debug (&c->bck_fc);
389 * Schedule next keepalive task, taking in consideration
390 * the connection state and number of retries.
392 * @param c Connection for which to schedule the next keepalive.
393 * @param fwd Direction for the next keepalive.
396 schedule_next_keepalive (struct CadetConnection *c, int fwd);
400 * Resets the connection timeout task, some other message has done the
402 * - For the first peer on the direction this means to send
403 * a keepalive or a path confirmation message (either create or ACK).
404 * - For all other peers, this means to destroy the connection,
405 * due to lack of activity.
406 * Starts the timeout if no timeout was running (connection just created).
408 * @param c Connection whose timeout to reset.
409 * @param fwd Is this forward?
412 connection_reset_timeout (struct CadetConnection *c, int fwd);
416 * Get string description for tunnel state. Reentrant.
418 * @param s Tunnel state.
420 * @return String representation.
423 GCC_state2s (enum CadetConnectionState s)
427 case CADET_CONNECTION_NEW:
428 return "CADET_CONNECTION_NEW";
429 case CADET_CONNECTION_SENT:
430 return "CADET_CONNECTION_SENT";
431 case CADET_CONNECTION_ACK:
432 return "CADET_CONNECTION_ACK";
433 case CADET_CONNECTION_READY:
434 return "CADET_CONNECTION_READY";
435 case CADET_CONNECTION_DESTROYED:
436 return "CADET_CONNECTION_DESTROYED";
437 case CADET_CONNECTION_BROKEN:
438 return "CADET_CONNECTION_BROKEN";
441 LOG (GNUNET_ERROR_TYPE_ERROR, " conn state %u unknown!\n", s);
442 return "CADET_CONNECTION_STATE_ERROR";
448 * Initialize a Flow Control structure to the initial state.
450 * @param fc Flow Control structure to initialize.
453 fc_init (struct CadetFlowControl *fc)
455 fc->next_pid = (uint32_t) 0;
456 fc->last_pid_sent = (uint32_t) -1;
457 fc->last_pid_recv = (uint32_t) -1;
458 fc->last_ack_sent = (uint32_t) 0;
459 fc->last_ack_recv = (uint32_t) 0;
460 fc->poll_task = NULL;
461 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
463 fc->queue_max = (max_msgs_queue / max_connections) + 1;
470 * @param cid Connection ID.
472 * @return conntection with the given ID @cid or NULL if not found.
474 static struct CadetConnection *
475 connection_get (const struct GNUNET_CADET_Hash *cid)
477 return GNUNET_CONTAINER_multihashmap_get (connections, GC_h2hc (cid));
482 * Change the connection state. Cannot change a connection marked as destroyed.
484 * @param c Connection to change.
485 * @param state New state to set.
488 connection_change_state (struct CadetConnection* c,
489 enum CadetConnectionState state)
491 LOG (GNUNET_ERROR_TYPE_DEBUG,
492 "Connection %s state %s -> %s\n",
493 GCC_2s (c), GCC_state2s (c->state), GCC_state2s (state));
494 if (CADET_CONNECTION_DESTROYED <= c->state) /* Destroyed or broken. */
496 LOG (GNUNET_ERROR_TYPE_DEBUG, "state not changing anymore\n");
500 if (CADET_CONNECTION_READY == state)
506 * Mark a connection as "destroyed", to send all pending traffic and freeing
507 * all associated resources, without accepting new status changes on it.
509 * @param c Connection to mark as destroyed.
512 mark_destroyed (struct CadetConnection *c)
514 c->destroy = GNUNET_YES;
515 connection_change_state (c, CADET_CONNECTION_DESTROYED);
520 * Function called if a connection has been stalled for a while,
521 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
523 * @param cls Closure (poll ctx).
526 send_poll (void *cls);
530 * Send an ACK on the connection, informing the predecessor about
531 * the available buffer space. Should not be called in case the peer
532 * is origin (no predecessor) in the @c fwd direction.
534 * Note that for fwd ack, the FWD mean forward *traffic* (root->dest),
535 * the ACK itself goes "back" (dest->root).
537 * @param c Connection on which to send the ACK.
538 * @param buffer How much space free to advertise?
539 * @param fwd Is this FWD ACK? (Going dest -> root)
540 * @param force Don't optimize out.
543 send_ack (struct CadetConnection *c, unsigned int buffer, int fwd, int force)
545 struct CadetFlowControl *next_fc;
546 struct CadetFlowControl *prev_fc;
547 struct GNUNET_CADET_ACK msg;
551 GCC_check_connections ();
552 GNUNET_assert (GNUNET_NO == GCC_is_origin (c, fwd));
554 next_fc = fwd ? &c->fwd_fc : &c->bck_fc;
555 prev_fc = fwd ? &c->bck_fc : &c->fwd_fc;
557 LOG (GNUNET_ERROR_TYPE_DEBUG, "send %s ack on %s\n",
558 GC_f2s (fwd), GCC_2s (c));
560 /* Check if we need to transmit the ACK. */
561 delta = prev_fc->last_ack_sent - prev_fc->last_pid_recv;
562 if (3 < delta && buffer < delta && GNUNET_NO == force)
564 LOG (GNUNET_ERROR_TYPE_DEBUG, "Not sending ACK, delta > 3\n");
565 LOG (GNUNET_ERROR_TYPE_DEBUG,
566 " last pid recv: %u, last ack sent: %u\n",
567 prev_fc->last_pid_recv, prev_fc->last_ack_sent);
568 GCC_check_connections ();
572 /* Ok, ACK might be necessary, what PID to ACK? */
573 ack = prev_fc->last_pid_recv + buffer;
574 LOG (GNUNET_ERROR_TYPE_DEBUG,
575 " ACK %u, last PID %u, last ACK %u, qmax %u, q %u\n",
576 ack, prev_fc->last_pid_recv, prev_fc->last_ack_sent,
577 next_fc->queue_max, next_fc->queue_n);
578 if (ack == prev_fc->last_ack_sent && GNUNET_NO == force)
580 LOG (GNUNET_ERROR_TYPE_DEBUG, "Not sending FWD ACK, not needed\n");
581 GCC_check_connections ();
585 /* Check if message is already in queue */
586 if (NULL != prev_fc->ack_msg)
588 if (GC_is_pid_bigger (ack, prev_fc->last_ack_sent))
590 LOG (GNUNET_ERROR_TYPE_DEBUG, " canceling old ACK\n");
591 GCC_cancel (prev_fc->ack_msg);
592 /* GCC_cancel triggers ack_sent(), which clears fc->ack_msg */
596 LOG (GNUNET_ERROR_TYPE_DEBUG, " same ACK already in queue\n");
597 GCC_check_connections ();
602 prev_fc->last_ack_sent = ack;
604 /* Build ACK message and send on conn */
605 msg.header.size = htons (sizeof (msg));
606 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_ACK);
607 msg.ack = htonl (ack);
610 prev_fc->ack_msg = GCC_send_prebuilt_message (&msg.header, UINT16_MAX, ack,
613 GNUNET_assert (NULL != prev_fc->ack_msg);
614 GCC_check_connections ();
619 * Update performance information if we are a connection's endpoint.
621 * @param c Connection to update.
622 * @param wait How much time did we wait to send the last message.
623 * @param size Size of the last message.
626 update_perf (struct CadetConnection *c,
627 struct GNUNET_TIME_Relative wait,
630 struct CadetConnectionPerformance *p;
634 return; /* Only endpoints are interested in timing. */
637 usecsperbyte = ((double) wait.rel_value_us) / size;
638 if (p->size == AVG_MSGS)
640 /* Array is full. Substract oldest value, add new one and store. */
641 p->avg -= (p->usecsperbyte[p->idx] / AVG_MSGS);
642 p->usecsperbyte[p->idx] = usecsperbyte;
643 p->avg += (p->usecsperbyte[p->idx] / AVG_MSGS);
647 /* Array not yet full. Add current value to avg and store. */
648 p->usecsperbyte[p->idx] = usecsperbyte;
650 p->avg += p->usecsperbyte[p->idx];
654 p->idx = (p->idx + 1) % AVG_MSGS;
659 * Callback called when a connection queued message is sent.
661 * Calculates the average time and connection packet tracking.
663 * @param cls Closure (ConnectionQueue Handle), can be NULL.
664 * @param c Connection this message was on.
665 * @param fwd Was this a FWD going message?
666 * @param sent Was it really sent? (Could have been canceled)
667 * @param type Type of message sent.
668 * @param payload_type Type of payload, if applicable.
669 * @param pid Message ID, or 0 if not applicable (create, destroy, etc).
670 * @param size Size of the message.
671 * @param wait Time spent waiting for core (only the time for THIS message)
674 conn_message_sent (void *cls,
675 struct CadetConnection *c, int fwd, int sent,
676 uint16_t type, uint16_t payload_type, uint32_t pid,
678 struct GNUNET_TIME_Relative wait)
680 struct CadetConnectionQueue *q = cls;
681 struct CadetFlowControl *fc;
684 GCC_check_connections ();
685 LOG (GNUNET_ERROR_TYPE_INFO,
686 ">>> %s (%s %4u) on conn %s (%p) %s [%5u] in queue %s\n",
687 GC_m2s (type), GC_m2s (payload_type), pid, GCC_2s (c), c,
689 GNUNET_STRINGS_relative_time_to_string (wait, GNUNET_YES));
691 /* If c is NULL, nothing to update. */
694 if (type != GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN
695 && type != GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY)
697 LOG (GNUNET_ERROR_TYPE_ERROR, "Message %s sent on NULL connection!\n",
700 GCC_check_connections ();
704 LOG (GNUNET_ERROR_TYPE_DEBUG, " %ssent %s %s pid %u\n",
705 sent ? "" : "not ", GC_f2s (fwd),
706 GC_m2s (type), GC_m2s (payload_type), pid);
707 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
709 /* Update flow control info. */
710 fc = fwd ? &c->fwd_fc : &c->bck_fc;
714 GNUNET_CONTAINER_DLL_remove (fc->q_head, fc->q_tail, q);
718 LOG (GNUNET_ERROR_TYPE_DEBUG, " calling cont\n");
719 q->cont (q->cont_cls, c, q, type, fwd, size);
723 else /* CONN_CREATE or CONN_ACK */
725 GNUNET_assert (GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED != type);
729 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P- %p %u\n", c, c->pending_messages);
730 c->pending_messages--;
731 if ( (GNUNET_YES == c->destroy) &&
732 (0 == c->pending_messages) )
734 LOG (GNUNET_ERROR_TYPE_DEBUG,
735 "! destroying connection!\n");
737 GCC_check_connections ();
741 /* Send ACK if needed, after accounting for sent ID in fc->queue_n */
744 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE:
745 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK:
746 c->maintenance_q = NULL;
747 /* Don't trigger a keepalive for sent ACKs, only SYN and SYNACKs */
748 if (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE == type || !fwd)
749 schedule_next_keepalive (c, fwd);
752 case GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED:
753 if (GNUNET_YES == sent)
755 fc->last_pid_sent = pid;
756 if (GC_is_pid_bigger (fc->last_pid_sent + 1, fc->last_ack_recv))
757 GCC_start_poll (c, fwd);
758 GCC_send_ack (c, fwd, GNUNET_NO);
759 connection_reset_timeout (c, fwd);
762 LOG (GNUNET_ERROR_TYPE_DEBUG, "! Q_N- %p %u\n", fc, fc->queue_n);
763 if (GNUNET_NO == forced)
766 LOG (GNUNET_ERROR_TYPE_DEBUG,
767 "! accounting pid %u\n",
772 LOG (GNUNET_ERROR_TYPE_DEBUG,
773 "! forced, Q_N not accounting pid %u\n",
778 case GNUNET_MESSAGE_TYPE_CADET_KX:
779 if (GNUNET_YES == sent)
780 connection_reset_timeout (c, fwd);
783 case GNUNET_MESSAGE_TYPE_CADET_POLL:
787 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL canceled on shutdown\n");
790 if (0 == fc->queue_max)
792 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL cancelled: neighbor disconnected\n");
795 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL sent for %s, scheduling new one!\n",
797 GNUNET_assert (NULL == fc->poll_task);
798 fc->poll_time = GNUNET_TIME_STD_BACKOFF (fc->poll_time);
799 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time,
801 LOG (GNUNET_ERROR_TYPE_DEBUG, " task %u\n", fc->poll_task);
804 case GNUNET_MESSAGE_TYPE_CADET_ACK:
808 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN:
809 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY:
813 LOG (GNUNET_ERROR_TYPE_ERROR, "%s unknown\n", GC_m2s (type));
817 LOG (GNUNET_ERROR_TYPE_DEBUG, "! message sent!\n");
819 update_perf (c, wait, size);
820 GCC_check_connections ();
825 * Get the previous hop in a connection
827 * @param c Connection.
829 * @return Previous peer in the connection.
831 static struct CadetPeer *
832 get_prev_hop (const struct CadetConnection *c)
838 LOG (GNUNET_ERROR_TYPE_DEBUG,
839 " get prev hop %s [%u/%u]\n",
840 GCC_2s (c), c->own_pos, c->path->length);
841 if (0 == c->own_pos || c->path->length < 2)
842 id = c->path->peers[0];
844 id = c->path->peers[c->own_pos - 1];
846 LOG (GNUNET_ERROR_TYPE_DEBUG, " ID: %s (%u)\n",
847 GNUNET_i2s (GNUNET_PEER_resolve2 (id)), id);
849 return GCP_get_short (id, GNUNET_YES);
854 * Get the next hop in a connection
856 * @param c Connection.
858 * @return Next peer in the connection.
860 static struct CadetPeer *
861 get_next_hop (const struct CadetConnection *c)
868 LOG (GNUNET_ERROR_TYPE_DEBUG, " get next hop %s [%u/%u]\n",
869 GCC_2s (c), c->own_pos, c->path->length);
870 if ((c->path->length - 1) == c->own_pos || c->path->length < 2)
871 id = c->path->peers[c->path->length - 1];
873 id = c->path->peers[c->own_pos + 1];
875 LOG (GNUNET_ERROR_TYPE_DEBUG, " ID: %s (%u)\n",
876 GNUNET_i2s (GNUNET_PEER_resolve2 (id)), id);
878 return GCP_get_short (id, GNUNET_YES);
883 * Check that the direct neighbours (previous and next hop)
884 * are properly associated with this connection.
886 * @param c connection to check
889 check_neighbours (const struct CadetConnection *c)
892 return; /* nothing to check */
893 GCP_check_connection (get_next_hop (c), c);
894 GCP_check_connection (get_prev_hop (c), c);
899 * Helper for #GCC_check_connections(). Calls #check_neighbours().
903 * @param value the `struct CadetConnection` to check
904 * @return #GNUNET_OK (continue to iterate)
907 check_connection (void *cls,
908 const struct GNUNET_HashCode *key,
911 struct CadetConnection *c = value;
913 check_neighbours (c);
919 * Check invariants for all connections using #check_neighbours().
922 GCC_check_connections ()
924 if (0 == CHECK_INVARIANTS)
926 if (NULL == connections)
928 GNUNET_CONTAINER_multihashmap_iterate (connections,
935 * Get the hop in a connection.
937 * @param c Connection.
938 * @param fwd Next in the FWD direction?
940 * @return Next peer in the connection.
942 static struct CadetPeer *
943 get_hop (struct CadetConnection *c, int fwd)
945 return (fwd) ? get_next_hop (c) : get_prev_hop (c);
950 * Get a bit mask for a message received out-of-order.
952 * @param last_pid_recv Last PID we received prior to the out-of-order.
953 * @param ooo_pid PID of the out-of-order message.
956 get_recv_bitmask (uint32_t last_pid_recv, uint32_t ooo_pid)
958 return 1 << (last_pid_recv - ooo_pid);
963 * Check is an out-of-order message is ok:
964 * - at most 31 messages behind.
967 * @param last_pid_recv Last in-order PID received.
970 is_ooo_ok (uint32_t last_pid_recv, uint32_t ooo_pid, uint32_t ooo_bitmap)
974 if (GC_is_pid_bigger (last_pid_recv - 31, ooo_pid))
977 mask = get_recv_bitmask (last_pid_recv, ooo_pid);
978 if (0 != (ooo_bitmap & mask))
986 * Is traffic coming from this sender 'FWD' traffic?
988 * @param c Connection to check.
989 * @param sender Short peer identity of neighbor.
991 * @return #GNUNET_YES in case the sender is the 'prev' hop and therefore
992 * the traffic is 'FWD'.
993 * #GNUNET_NO for BCK.
994 * #GNUNET_SYSERR for errors (sender isn't a hop in the connection).
997 is_fwd (const struct CadetConnection *c,
998 const struct CadetPeer *sender)
1002 id = GCP_get_short_id (sender);
1003 if (GCP_get_short_id (get_prev_hop (c)) == id)
1006 if (GCP_get_short_id (get_next_hop (c)) == id)
1009 return GNUNET_SYSERR;
1014 * Sends a CONNECTION ACK message in reponse to a received CONNECTION_CREATE
1015 * or a first CONNECTION_ACK directed to us.
1017 * @param c Connection to confirm.
1018 * @param fwd Should we send it FWD? (root->dest)
1019 * (First (~SYNACK) goes BCK, second (~ACK) goes FWD)
1022 send_connection_ack (struct CadetConnection *c, int fwd)
1024 struct GNUNET_CADET_ConnectionACK msg;
1025 struct CadetTunnel *t;
1026 const uint16_t size = sizeof (struct GNUNET_CADET_ConnectionACK);
1027 const uint16_t type = GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK;
1029 GCC_check_connections ();
1031 LOG (GNUNET_ERROR_TYPE_INFO,
1032 "==> %s ({ C %s ACK} 0) on conn %s (%p) %s [%5u]\n",
1033 GC_m2s (type), GC_f2s (!fwd), GCC_2s (c), c, GC_f2s (fwd), size);
1035 msg.header.size = htons (size);
1036 msg.header.type = htons (type);
1037 msg.reserved = htonl (0);
1040 GNUNET_assert (NULL == c->maintenance_q);
1041 c->maintenance_q = GCP_send (get_hop (c, fwd), &msg.header,
1042 GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK, 0,
1044 &conn_message_sent, NULL);
1045 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %p %u (conn`ACK)\n",
1046 c, c->pending_messages);
1047 c->pending_messages++;
1049 if (CADET_TUNNEL_NEW == GCT_get_cstate (t))
1050 GCT_change_cstate (t, CADET_TUNNEL_WAITING);
1051 if (CADET_CONNECTION_READY != c->state)
1052 connection_change_state (c, CADET_CONNECTION_SENT);
1053 GCC_check_connections ();
1058 * Send a notification that a connection is broken.
1060 * @param c Connection that is broken.
1061 * @param id1 Peer that has disconnected.
1062 * @param id2 Peer that has disconnected.
1063 * @param fwd Direction towards which to send it.
1066 send_broken (struct CadetConnection *c,
1067 const struct GNUNET_PeerIdentity *id1,
1068 const struct GNUNET_PeerIdentity *id2,
1071 struct GNUNET_CADET_ConnectionBroken msg;
1073 GCC_check_connections ();
1074 msg.header.size = htons (sizeof (struct GNUNET_CADET_ConnectionBroken));
1075 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN);
1077 msg.reserved = htonl (0);
1080 (void) GCC_send_prebuilt_message (&msg.header, UINT16_MAX, 0, c, fwd,
1081 GNUNET_YES, NULL, NULL);
1082 GCC_check_connections ();
1087 * Send a notification that a connection is broken, when a connection
1088 * isn't even known to the local peer or soon to be destroyed.
1090 * @param connection_id Connection ID.
1091 * @param id1 Peer that has disconnected, probably local peer.
1092 * @param id2 Peer that has disconnected can be NULL if unknown.
1093 * @param neighbor Peer to notify (neighbor who sent the connection).
1096 send_broken_unknown (const struct GNUNET_CADET_Hash *connection_id,
1097 const struct GNUNET_PeerIdentity *id1,
1098 const struct GNUNET_PeerIdentity *id2,
1099 struct CadetPeer *neighbor)
1101 struct GNUNET_CADET_ConnectionBroken msg;
1103 GCC_check_connections ();
1104 LOG (GNUNET_ERROR_TYPE_INFO, "--> BROKEN on unknown connection %s\n",
1105 GNUNET_h2s (GC_h2hc (connection_id)));
1107 msg.header.size = htons (sizeof (struct GNUNET_CADET_ConnectionBroken));
1108 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN);
1109 msg.cid = *connection_id;
1110 msg.reserved = htonl (0);
1115 memset (&msg.peer2, 0, sizeof (msg.peer2));
1116 GNUNET_assert (NULL != GCP_send (neighbor, &msg.header,
1118 NULL, GNUNET_SYSERR, /* connection, fwd */
1119 NULL, NULL)); /* continuation */
1120 GCC_check_connections ();
1125 * Send keepalive packets for a connection.
1127 * @param c Connection to keep alive..
1128 * @param fwd Is this a FWD keepalive? (owner -> dest).
1131 send_connection_keepalive (struct CadetConnection *c, int fwd)
1133 struct GNUNET_MessageHeader msg;
1134 struct CadetFlowControl *fc;
1137 GCC_check_connections ();
1138 LOG (GNUNET_ERROR_TYPE_INFO,
1139 "keepalive %s for connection %s\n",
1140 GC_f2s (fwd), GCC_2s (c));
1142 GNUNET_assert (NULL != c->t);
1143 fc = fwd ? &c->fwd_fc : &c->bck_fc;
1144 tunnel_ready = GNUNET_YES == GCT_has_queued_traffic (c->t)
1145 && CADET_TUNNEL_KEY_OK <= GCT_get_estate (c->t);
1146 if (0 < fc->queue_n || tunnel_ready)
1148 LOG (GNUNET_ERROR_TYPE_INFO, "not sending keepalive, traffic in queue\n");
1152 GNUNET_STATISTICS_update (stats, "# keepalives sent", 1, GNUNET_NO);
1154 GNUNET_assert (NULL != c->t);
1155 msg.size = htons (sizeof (msg));
1156 msg.type = htons (GNUNET_MESSAGE_TYPE_CADET_KEEPALIVE);
1158 GNUNET_assert (NULL ==
1159 GCT_send_prebuilt_message (&msg, c->t, c,
1160 GNUNET_NO, NULL, NULL));
1161 GCC_check_connections ();
1166 * Send CONNECTION_{CREATE/ACK} packets for a connection.
1168 * @param c Connection for which to send the message.
1169 * @param fwd If #GNUNET_YES, send CREATE, otherwise send ACK.
1172 connection_recreate (struct CadetConnection *c, int fwd)
1174 LOG (GNUNET_ERROR_TYPE_DEBUG,
1175 "sending connection recreate\n");
1177 GCC_send_create (c);
1179 send_connection_ack (c, GNUNET_NO);
1184 * Generic connection timer management.
1185 * Depending on the role of the peer in the connection will send the
1186 * appropriate message (build or keepalive)
1188 * @param c Conncetion to maintain.
1189 * @param fwd Is FWD?
1192 connection_maintain (struct CadetConnection *c, int fwd)
1194 if (GNUNET_NO != c->destroy)
1196 LOG (GNUNET_ERROR_TYPE_INFO, "not sending keepalive, being destroyed\n");
1203 GCC_debug (c, GNUNET_ERROR_TYPE_ERROR);
1207 if (CADET_TUNNEL_SEARCHING == GCT_get_cstate (c->t))
1209 /* If status is SEARCHING, why is there a connection? Should be WAITING */
1211 GCT_debug (c->t, GNUNET_ERROR_TYPE_ERROR);
1212 LOG (GNUNET_ERROR_TYPE_INFO, "not sending keepalive, tunnel SEARCHING\n");
1213 schedule_next_keepalive (c, fwd);
1218 case CADET_CONNECTION_NEW:
1221 case CADET_CONNECTION_SENT:
1222 connection_recreate (c, fwd);
1224 case CADET_CONNECTION_READY:
1225 send_connection_keepalive (c, fwd);
1234 * Keep the connection alive.
1236 * @param c Connection to keep alive.
1237 * @param fwd Direction.
1240 connection_keepalive (struct CadetConnection *c,
1243 GCC_check_connections ();
1244 LOG (GNUNET_ERROR_TYPE_DEBUG,
1245 "%s keepalive for %s\n",
1246 GC_f2s (fwd), GCC_2s (c));
1249 c->fwd_maintenance_task = NULL;
1251 c->bck_maintenance_task = NULL;
1252 connection_maintain (c, fwd);
1253 GCC_check_connections ();
1254 /* Next execution will be scheduled by message_sent or _maintain*/
1259 * Keep the connection alive in the FWD direction.
1261 * @param cls Closure (connection to keepalive).
1264 connection_fwd_keepalive (void *cls)
1266 struct CadetConnection *c = cls;
1268 GCC_check_connections ();
1269 connection_keepalive (c,
1271 GCC_check_connections ();
1276 * Keep the connection alive in the BCK direction.
1278 * @param cls Closure (connection to keepalive).
1281 connection_bck_keepalive (void *cls)
1283 struct CadetConnection *c = cls;
1285 GCC_check_connections ();
1286 connection_keepalive (c,
1288 GCC_check_connections ();
1293 * Schedule next keepalive task, taking in consideration
1294 * the connection state and number of retries.
1296 * If the peer is not the origin, do nothing.
1298 * @param c Connection for which to schedule the next keepalive.
1299 * @param fwd Direction for the next keepalive.
1302 schedule_next_keepalive (struct CadetConnection *c, int fwd)
1304 struct GNUNET_TIME_Relative delay;
1305 struct GNUNET_SCHEDULER_Task * *task_id;
1306 GNUNET_SCHEDULER_TaskCallback keepalive_task;
1308 GCC_check_connections ();
1309 if (GNUNET_NO == GCC_is_origin (c, fwd))
1312 /* Calculate delay to use, depending on the state of the connection */
1313 if (CADET_CONNECTION_READY == c->state)
1315 delay = refresh_connection_time;
1319 if (1 > c->create_retry)
1320 c->create_retry = 1;
1321 delay = GNUNET_TIME_relative_saturating_multiply (create_connection_time,
1323 if (c->create_retry < 64) // TODO make configurable
1324 c->create_retry *= 2;
1327 /* Select direction-dependent parameters */
1328 if (GNUNET_YES == fwd)
1330 task_id = &c->fwd_maintenance_task;
1331 keepalive_task = &connection_fwd_keepalive;
1335 task_id = &c->bck_maintenance_task;
1336 keepalive_task = &connection_bck_keepalive;
1339 /* Check that no one scheduled it before us */
1340 if (NULL != *task_id)
1342 /* No need for a _break. It can happen for instance when sending a SYNACK
1343 * for a duplicate SYN: the first SYNACK scheduled the task. */
1344 GNUNET_SCHEDULER_cancel (*task_id);
1347 /* Schedule the task */
1348 *task_id = GNUNET_SCHEDULER_add_delayed (delay,
1351 LOG (GNUNET_ERROR_TYPE_INFO,
1352 "next keepalive for %s in in %s\n",
1353 GCC_2s (c), GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_YES));
1354 GCC_check_connections ();
1359 * Cancel all transmissions that belong to a certain connection.
1361 * If the connection is scheduled for destruction and no more messages are left,
1362 * the connection will be destroyed by the continuation call.
1364 * @param c Connection which to cancel. Might be destroyed during this call.
1365 * @param fwd Cancel fwd traffic?
1368 connection_cancel_queues (struct CadetConnection *c,
1371 struct CadetFlowControl *fc;
1373 GCC_check_connections ();
1374 LOG (GNUNET_ERROR_TYPE_DEBUG,
1375 "Cancel %s queues for connection %s\n",
1376 GC_f2s (fwd), GCC_2s (c));
1383 fc = fwd ? &c->fwd_fc : &c->bck_fc;
1384 if (NULL != fc->poll_task)
1386 GNUNET_SCHEDULER_cancel (fc->poll_task);
1387 fc->poll_task = NULL;
1388 LOG (GNUNET_ERROR_TYPE_DEBUG, " cancelled POLL task for fc %p\n", fc);
1390 if (NULL != fc->poll_msg)
1392 GCC_cancel (fc->poll_msg);
1393 LOG (GNUNET_ERROR_TYPE_DEBUG, " cancelled POLL msg for fc %p\n", fc);
1396 while (NULL != fc->q_head)
1398 GCC_cancel (fc->q_head);
1400 GCC_check_connections ();
1405 * Function called if a connection has been stalled for a while,
1406 * possibly due to a missed ACK. Poll the neighbor about its ACK status.
1408 * @param cls Closure (poll ctx).
1411 send_poll (void *cls)
1413 struct CadetFlowControl *fc = cls;
1414 struct GNUNET_CADET_Poll msg;
1415 struct CadetConnection *c;
1418 fc->poll_task = NULL;
1419 GCC_check_connections ();
1421 fwd = fc == &c->fwd_fc;
1422 LOG (GNUNET_ERROR_TYPE_DEBUG, "Polling connection %s %s\n",
1423 GCC_2s (c), GC_f2s (fwd));
1425 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_POLL);
1426 msg.header.size = htons (sizeof (msg));
1428 msg.pid = htonl (fc->last_pid_sent);
1429 LOG (GNUNET_ERROR_TYPE_DEBUG, " last pid sent: %u\n", fc->last_pid_sent);
1431 GCC_send_prebuilt_message (&msg.header, UINT16_MAX, fc->last_pid_sent, c,
1432 fc == &c->fwd_fc, GNUNET_YES, NULL, NULL);
1433 GNUNET_assert (NULL != fc->poll_msg);
1434 GCC_check_connections ();
1439 * Generic connection timeout implementation.
1441 * Timeout function due to lack of keepalive/traffic from an endpoint.
1442 * Destroys connection if called.
1444 * @param c Connection to destroy.
1445 * @param fwd Was the timeout from the origin? (FWD timeout)
1448 connection_timeout (struct CadetConnection *c, int fwd)
1450 GCC_check_connections ();
1452 LOG (GNUNET_ERROR_TYPE_INFO,
1453 "Connection %s %s timed out. Destroying.\n",
1456 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
1458 if (GCC_is_origin (c, fwd)) /* Loopback? Something is wrong! */
1464 /* If dest, send "broken" notification. */
1465 if (GCC_is_terminal (c, fwd))
1467 struct CadetPeer *next_hop;
1469 next_hop = fwd ? get_prev_hop (c) : get_next_hop (c);
1470 send_broken_unknown (&c->id, &my_full_id, NULL, next_hop);
1474 GCC_check_connections ();
1479 * Timeout function due to lack of keepalive/traffic from the owner.
1480 * Destroys connection if called.
1482 * @param cls Closure (connection to destroy).
1485 connection_fwd_timeout (void *cls)
1487 struct CadetConnection *c = cls;
1489 c->fwd_maintenance_task = NULL;
1490 GCC_check_connections ();
1491 connection_timeout (c, GNUNET_YES);
1492 GCC_check_connections ();
1497 * Timeout function due to lack of keepalive/traffic from the destination.
1498 * Destroys connection if called.
1500 * @param cls Closure (connection to destroy).
1503 connection_bck_timeout (void *cls)
1505 struct CadetConnection *c = cls;
1507 c->bck_maintenance_task = NULL;
1508 GCC_check_connections ();
1509 connection_timeout (c, GNUNET_NO);
1510 GCC_check_connections ();
1515 * Resets the connection timeout task, some other message has done the
1517 * - For the first peer on the direction this means to send
1518 * a keepalive or a path confirmation message (either create or ACK).
1519 * - For all other peers, this means to destroy the connection,
1520 * due to lack of activity.
1521 * Starts the timeout if no timeout was running (connection just created).
1523 * @param c Connection whose timeout to reset.
1524 * @param fwd Is this forward?
1526 * TODO use heap to improve efficiency of scheduler.
1529 connection_reset_timeout (struct CadetConnection *c, int fwd)
1531 LOG (GNUNET_ERROR_TYPE_DEBUG, "Connection %s reset timeout\n", GC_f2s (fwd));
1532 if (GCC_is_origin (c, fwd)) /* Startpoint */
1534 schedule_next_keepalive (c, fwd);
1535 if (NULL != c->maintenance_q)
1537 GCP_send_cancel (c->maintenance_q);
1538 c->maintenance_q = NULL; /* Is set to NULL by conn_message_sent anyway */
1541 else /* Relay, endpoint. */
1543 struct GNUNET_TIME_Relative delay;
1544 struct GNUNET_SCHEDULER_Task * *ti;
1545 GNUNET_SCHEDULER_TaskCallback f;
1547 ti = fwd ? &c->fwd_maintenance_task : &c->bck_maintenance_task;
1550 GNUNET_SCHEDULER_cancel (*ti);
1551 delay = GNUNET_TIME_relative_saturating_multiply (refresh_connection_time, 4);
1552 LOG (GNUNET_ERROR_TYPE_DEBUG,
1553 " timing out in %s\n",
1554 GNUNET_STRINGS_relative_time_to_string (delay, GNUNET_NO));
1555 f = fwd ? &connection_fwd_timeout : &connection_bck_timeout;
1556 *ti = GNUNET_SCHEDULER_add_delayed (delay, f, c);
1562 * Iterator to compare each connection's path with the path of a new connection.
1564 * If the connection coincides, the c member of path is set to the connection
1565 * and the destroy flag of the connection is set.
1567 * @param cls Closure (new path).
1568 * @param c Connection in the tunnel to check.
1571 check_path (void *cls, struct CadetConnection *c)
1573 struct CadetConnection *new_conn = cls;
1574 struct CadetPeerPath *path = new_conn->path;
1576 LOG (GNUNET_ERROR_TYPE_DEBUG, " checking %s (%p), length %u\n",
1577 GCC_2s (c), c, c->path->length);
1580 && GNUNET_NO == c->destroy
1581 && CADET_CONNECTION_BROKEN != c->state
1582 && CADET_CONNECTION_DESTROYED != c->state
1583 && path_equivalent (path, c->path))
1585 new_conn->destroy = GNUNET_YES; /* Do not mark_destroyed, */
1586 new_conn->path->c = c; /* this is only a flag for the Iterator. */
1587 LOG (GNUNET_ERROR_TYPE_DEBUG, " MATCH!\n");
1593 * Finds out if this path is already being used by an existing connection.
1595 * Checks the tunnel towards the destination to see if it contains
1596 * any connection with the same path.
1598 * If the existing connection is ready, it is kept.
1599 * Otherwise if the sender has a smaller ID that ours, we accept it (and
1600 * the peer will eventually reject our attempt).
1602 * @param path Path to check.
1603 * @return #GNUNET_YES if the tunnel has a connection with the same path,
1604 * #GNUNET_NO otherwise.
1607 does_connection_exist (struct CadetConnection *conn)
1609 struct CadetPeer *p;
1610 struct CadetTunnel *t;
1611 struct CadetConnection *c;
1613 p = GCP_get_short (conn->path->peers[0], GNUNET_NO);
1616 t = GCP_get_tunnel (p);
1620 LOG (GNUNET_ERROR_TYPE_DEBUG, "Checking for duplicates\n");
1622 GCT_iterate_connections (t, &check_path, conn);
1624 if (GNUNET_YES == conn->destroy)
1627 conn->destroy = GNUNET_NO;
1628 conn->path->c = conn;
1629 LOG (GNUNET_ERROR_TYPE_DEBUG, " found duplicate of %s\n", GCC_2s (conn));
1630 LOG (GNUNET_ERROR_TYPE_DEBUG, " duplicate: %s\n", GCC_2s (c));
1631 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
1632 if (CADET_CONNECTION_READY == c->state)
1634 /* The other peer confirmed a live connection with this path,
1635 * why are they trying to duplicate it? */
1636 GNUNET_STATISTICS_update (stats, "# duplicate connections", 1, GNUNET_NO);
1639 LOG (GNUNET_ERROR_TYPE_DEBUG, " duplicate not ready, connection unique\n");
1644 LOG (GNUNET_ERROR_TYPE_DEBUG, " %s has no duplicates\n", GCC_2s (conn));
1651 * @brief Check if the tunnel this connection belongs to has any other
1652 * connection with the same path, and destroy one if so.
1654 * @param cls Closure (connection to check).
1657 check_duplicates (void *cls)
1659 struct CadetConnection *c = cls;
1661 c->check_duplicates_task = NULL;
1662 if (GNUNET_YES == does_connection_exist (c))
1664 GCT_debug (c->t, GNUNET_ERROR_TYPE_DEBUG);
1665 send_broken (c, &my_full_id, &my_full_id, GCC_is_origin (c, GNUNET_YES));
1672 * Wait for enough time to let any dead connections time out and check for
1673 * any remaining duplicates.
1675 * @param c Connection that is a potential duplicate.
1678 schedule_check_duplicates (struct CadetConnection *c)
1680 struct GNUNET_TIME_Relative delay;
1682 if (NULL != c->check_duplicates_task)
1684 delay = GNUNET_TIME_relative_saturating_multiply (refresh_connection_time, 5);
1685 c->check_duplicates_task = GNUNET_SCHEDULER_add_delayed (delay,
1692 * Add the connection to the list of both neighbors.
1694 * @param c Connection.
1696 * @return #GNUNET_OK if everything went fine
1697 * #GNUNET_SYSERR if the was an error and @c c is malformed.
1700 register_neighbors (struct CadetConnection *c)
1702 c->next_peer = get_next_hop (c);
1703 c->prev_peer = get_prev_hop (c);
1704 GNUNET_assert (c->next_peer != c->prev_peer);
1705 LOG (GNUNET_ERROR_TYPE_DEBUG,
1706 "register neighbors for connection %s\n",
1708 path_debug (c->path);
1709 LOG (GNUNET_ERROR_TYPE_DEBUG,
1710 "own pos %u\n", c->own_pos);
1711 LOG (GNUNET_ERROR_TYPE_DEBUG,
1712 "putting connection %s to next peer %p\n",
1715 LOG (GNUNET_ERROR_TYPE_DEBUG, "next peer %p %s\n",
1717 GCP_2s (c->next_peer));
1718 LOG (GNUNET_ERROR_TYPE_DEBUG,
1719 "putting connection %s to prev peer %p\n",
1722 LOG (GNUNET_ERROR_TYPE_DEBUG,
1723 "prev peer %p %s\n",
1725 GCP_2s (c->prev_peer));
1727 if ( (GNUNET_NO == GCP_is_neighbor (c->next_peer)) ||
1728 (GNUNET_NO == GCP_is_neighbor (c->prev_peer)) )
1730 if (GCC_is_origin (c, GNUNET_YES))
1731 GNUNET_STATISTICS_update (stats, "# local bad paths", 1, GNUNET_NO);
1732 GNUNET_STATISTICS_update (stats, "# bad paths", 1, GNUNET_NO);
1734 LOG (GNUNET_ERROR_TYPE_DEBUG,
1735 " register neighbors failed\n");
1736 LOG (GNUNET_ERROR_TYPE_DEBUG,
1737 " prev: %s, neighbor?: %d\n",
1738 GCP_2s (c->prev_peer),
1739 GCP_is_neighbor (c->prev_peer));
1740 LOG (GNUNET_ERROR_TYPE_DEBUG,
1741 " next: %s, neighbor?: %d\n",
1742 GCP_2s (c->next_peer),
1743 GCP_is_neighbor (c->next_peer));
1744 return GNUNET_SYSERR;
1746 GCP_add_connection (c->next_peer, c, GNUNET_NO);
1747 GCP_add_connection (c->prev_peer, c, GNUNET_YES);
1754 * Remove the connection from the list of both neighbors.
1756 * @param c Connection.
1759 unregister_neighbors (struct CadetConnection *c)
1761 // struct CadetPeer *peer; FIXME dont use next_peer, prev_peer
1762 /* Either already unregistered or never got registered, it's ok either way. */
1763 if (NULL == c->path)
1765 if (NULL != c->next_peer)
1767 GCP_remove_connection (c->next_peer, c);
1768 c->next_peer = NULL;
1770 if (NULL != c->prev_peer)
1772 GCP_remove_connection (c->prev_peer, c);
1773 c->prev_peer = NULL;
1779 * Invalidates all paths towards all peers that comprise the connection which
1780 * rely on the disconnected peer.
1782 * ~O(n^3) (peers in connection * paths/peer * links/path)
1784 * @param c Connection whose peers' paths to clean.
1785 * @param disconnected Peer that disconnected.
1788 invalidate_paths (struct CadetConnection *c,
1789 struct CadetPeer *disconnected)
1791 struct CadetPeer *peer;
1794 for (i = 0; i < c->path->length; i++)
1796 peer = GCP_get_short (c->path->peers[i], GNUNET_NO);
1798 GCP_notify_broken_link (peer, &my_full_id, GCP_get_id (disconnected));
1804 * Bind the connection to the peer and the tunnel to that peer.
1806 * If the peer has no tunnel, create one. Update tunnel and connection
1807 * data structres to reflect new status.
1809 * @param c Connection.
1813 add_to_peer (struct CadetConnection *c,
1814 struct CadetPeer *peer)
1816 GCP_add_tunnel (peer);
1817 c->t = GCP_get_tunnel (peer);
1818 GCT_add_connection (c->t, c);
1823 * Log receipt of message on stderr (INFO level).
1825 * @param message Message received.
1826 * @param peer Peer who sent the message.
1827 * @param conn_id Connection ID of the message.
1830 log_message (const struct GNUNET_MessageHeader *message,
1831 const struct CadetPeer *peer,
1832 const struct GNUNET_CADET_Hash *conn_id)
1838 size = ntohs (message->size);
1839 type = ntohs (message->type);
1842 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE:
1843 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK:
1844 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN:
1845 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY:
1851 LOG (GNUNET_ERROR_TYPE_INFO, "<%s %s on conn %s from %s, %6u bytes\n",
1852 arrow, GC_m2s (type), GNUNET_h2s (GC_h2hc (conn_id)),
1853 GCP_2s(peer), (unsigned int) size);
1856 /******************************************************************************/
1857 /******************************** API ***********************************/
1858 /******************************************************************************/
1861 * Handler for connection creation.
1863 * @param peer Message sender (neighbor).
1864 * @param msg Message itself.
1867 GCC_handle_create (struct CadetPeer *peer,
1868 const struct GNUNET_CADET_ConnectionCreate *msg)
1870 const struct GNUNET_CADET_Hash *cid;
1871 struct GNUNET_PeerIdentity *id;
1872 struct CadetPeerPath *path;
1873 struct CadetPeer *dest_peer;
1874 struct CadetPeer *orig_peer;
1875 struct CadetConnection *c;
1876 unsigned int own_pos;
1879 GCC_check_connections ();
1880 size = ntohs (msg->header.size);
1882 /* Calculate hops */
1883 size -= sizeof (struct GNUNET_CADET_ConnectionCreate);
1884 if (0 != size % sizeof (struct GNUNET_PeerIdentity))
1886 GNUNET_break_op (0);
1889 size /= sizeof (struct GNUNET_PeerIdentity);
1892 GNUNET_break_op (0);
1895 LOG (GNUNET_ERROR_TYPE_DEBUG, " path has %u hops.\n", size);
1897 /* Get parameters */
1899 log_message (&msg->header, peer, cid);
1900 id = (struct GNUNET_PeerIdentity *) &msg[1];
1901 LOG (GNUNET_ERROR_TYPE_DEBUG, " origin: %s\n", GNUNET_i2s (id));
1903 /* Create connection */
1904 c = connection_get (cid);
1907 path = path_build_from_peer_ids ((struct GNUNET_PeerIdentity *) &msg[1],
1908 size, myid, &own_pos);
1911 /* Path was malformed, probably our own ID was not in it. */
1912 GNUNET_STATISTICS_update (stats, "# malformed paths", 1, GNUNET_NO);
1913 GNUNET_break_op (0);
1918 /* We received this request from a neighbor, we cannot be origin */
1919 GNUNET_STATISTICS_update (stats, "# fake paths", 1, GNUNET_NO);
1920 GNUNET_break_op (0);
1921 path_destroy (path);
1925 LOG (GNUNET_ERROR_TYPE_DEBUG, " Own position: %u\n", own_pos);
1926 LOG (GNUNET_ERROR_TYPE_DEBUG, " Creating connection\n");
1927 c = GCC_new (cid, NULL, path, own_pos);
1930 if (path->length - 1 == own_pos)
1932 /* If we are destination, why did the creation fail? */
1934 path_destroy (path);
1935 GCC_check_connections ();
1938 send_broken_unknown (cid, &my_full_id,
1939 GNUNET_PEER_resolve2 (path->peers[own_pos + 1]),
1941 path_destroy (path);
1942 GCC_check_connections ();
1945 GCP_add_path_to_all (path, GNUNET_NO);
1946 connection_reset_timeout (c, GNUNET_YES);
1950 path = path_duplicate (c->path);
1952 if (CADET_CONNECTION_NEW == c->state)
1953 connection_change_state (c, CADET_CONNECTION_SENT);
1955 /* Remember peers */
1956 dest_peer = GCP_get (&id[size - 1], GNUNET_YES);
1957 orig_peer = GCP_get (&id[0], GNUNET_YES);
1959 /* Is it a connection to us? */
1960 if (c->own_pos == path->length - 1)
1962 LOG (GNUNET_ERROR_TYPE_DEBUG, " It's for us!\n");
1963 GCP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_YES);
1965 add_to_peer (c, orig_peer);
1966 if (GNUNET_YES == does_connection_exist (c))
1968 /* Peer created a connection equal to one we think exists
1970 * Solution: Keep both and postpone disambiguation. In the meantime
1971 * the connection will time out or peer will inform us it is broken.
1974 * - Use explicit duplicate.
1975 * - Accept new conn and destroy the old. (interruption in higher level)
1976 * - Keep the one with higher ID / created by peer with higher ID. */
1977 schedule_check_duplicates (c);
1980 if (CADET_TUNNEL_NEW == GCT_get_cstate (c->t))
1981 GCT_change_cstate (c->t, CADET_TUNNEL_WAITING);
1982 if (NULL == c->maintenance_q)
1983 send_connection_ack (c, GNUNET_NO);
1984 if (CADET_CONNECTION_SENT == c->state)
1985 connection_change_state (c, CADET_CONNECTION_ACK);
1989 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
1990 GCP_add_path (dest_peer, path_duplicate (path), GNUNET_NO);
1991 GCP_add_path_to_origin (orig_peer, path_duplicate (path), GNUNET_NO);
1992 (void) GCC_send_prebuilt_message (&msg->header, 0, 0, c,
1993 GNUNET_YES, GNUNET_YES, NULL, NULL);
1995 path_destroy (path);
1996 GCC_check_connections ();
2001 * Handler for connection confirmations.
2003 * @param peer Message sender (neighbor).
2004 * @param msg Message itself.
2007 GCC_handle_confirm (struct CadetPeer *peer,
2008 const struct GNUNET_CADET_ConnectionACK *msg)
2010 struct CadetConnection *c;
2011 enum CadetConnectionState oldstate;
2014 GCC_check_connections ();
2015 log_message (&msg->header, peer, &msg->cid);
2016 c = connection_get (&msg->cid);
2019 GNUNET_STATISTICS_update (stats, "# control on unknown connection",
2021 LOG (GNUNET_ERROR_TYPE_DEBUG,
2022 " don't know the connection!\n");
2023 send_broken_unknown (&msg->cid, &my_full_id, NULL, peer);
2024 GCC_check_connections ();
2027 if (GNUNET_NO != c->destroy)
2029 GNUNET_assert (CADET_CONNECTION_DESTROYED == c->state);
2030 GNUNET_STATISTICS_update (stats, "# control on dying connection",
2032 LOG (GNUNET_ERROR_TYPE_DEBUG,
2033 "connection %s being destroyed, ignoring confirm\n",
2035 GCC_check_connections ();
2039 oldstate = c->state;
2040 LOG (GNUNET_ERROR_TYPE_DEBUG, " via peer %s\n", GCP_2s (peer));
2041 if (get_next_hop (c) == peer)
2043 LOG (GNUNET_ERROR_TYPE_DEBUG, " SYNACK\n");
2045 if (CADET_CONNECTION_SENT == oldstate)
2046 connection_change_state (c, CADET_CONNECTION_ACK);
2048 else if (get_prev_hop (c) == peer)
2050 LOG (GNUNET_ERROR_TYPE_DEBUG, " FINAL ACK\n");
2052 connection_change_state (c, CADET_CONNECTION_READY);
2056 GNUNET_STATISTICS_update (stats, "# control on connection from wrong peer",
2058 GNUNET_break_op (0);
2062 connection_reset_timeout (c, fwd);
2064 GNUNET_assert (NULL != c->path);
2065 GCP_add_path_to_all (c->path, GNUNET_YES);
2067 /* Message for us as creator? */
2068 if (GNUNET_YES == GCC_is_origin (c, GNUNET_YES))
2070 if (GNUNET_NO != fwd)
2075 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection (SYN)ACK for us!\n");
2077 /* If just created, cancel the short timeout and start a long one */
2078 if (CADET_CONNECTION_SENT == oldstate)
2080 c->create_retry = 1;
2081 connection_reset_timeout (c, GNUNET_YES);
2084 /* Change connection state, send ACK */
2085 connection_change_state (c, CADET_CONNECTION_READY);
2086 send_connection_ack (c, GNUNET_YES);
2088 /* Change tunnel state, trigger KX */
2089 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
2090 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
2091 GCC_check_connections ();
2095 /* Message for us as destination? */
2096 if (GCC_is_terminal (c, GNUNET_YES))
2098 if (GNUNET_YES != fwd)
2103 LOG (GNUNET_ERROR_TYPE_DEBUG, " Connection ACK for us!\n");
2105 /* If just created, cancel the short timeout and start a long one */
2106 if (CADET_CONNECTION_ACK == oldstate)
2107 connection_reset_timeout (c, GNUNET_NO);
2109 /* Change tunnel state */
2110 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
2111 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
2112 GCC_check_connections ();
2116 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2117 (void) GCC_send_prebuilt_message (&msg->header, 0, 0, c, fwd,
2118 GNUNET_YES, NULL, NULL);
2120 GCC_check_connections ();
2125 * Handler for notifications of broken connections.
2127 * @param peer Message sender (neighbor).
2128 * @param msg Message itself.
2131 GCC_handle_broken (struct CadetPeer *peer,
2132 const struct GNUNET_CADET_ConnectionBroken *msg)
2134 struct CadetConnection *c;
2135 struct CadetTunnel *t;
2138 GCC_check_connections ();
2139 log_message (&msg->header, peer, &msg->cid);
2140 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n", GNUNET_i2s (&msg->peer1));
2141 LOG (GNUNET_ERROR_TYPE_DEBUG, " regarding %s\n", GNUNET_i2s (&msg->peer2));
2142 c = connection_get (&msg->cid);
2145 LOG (GNUNET_ERROR_TYPE_DEBUG, " duplicate CONNECTION_BROKEN\n");
2146 GNUNET_STATISTICS_update (stats, "# duplicate CONNECTION_BROKEN",
2148 GCC_check_connections ();
2154 fwd = is_fwd (c, peer);
2155 if (GNUNET_SYSERR == fwd)
2157 GNUNET_break_op (0);
2158 GCC_check_connections ();
2162 if (GCC_is_terminal (c, fwd))
2164 struct CadetPeer *endpoint;
2168 /* A terminal connection should not have 't' set to NULL. */
2170 GCC_debug (c, GNUNET_ERROR_TYPE_ERROR);
2173 endpoint = GCP_get_short (c->path->peers[c->path->length - 1], GNUNET_YES);
2174 if (2 < c->path->length)
2175 path_invalidate (c->path);
2176 GCP_notify_broken_link (endpoint, &msg->peer1, &msg->peer2);
2178 connection_change_state (c, CADET_CONNECTION_BROKEN);
2179 GCT_remove_connection (t, c);
2186 (void) GCC_send_prebuilt_message (&msg->header, 0, 0, c, fwd,
2187 GNUNET_YES, NULL, NULL);
2188 connection_cancel_queues (c, !fwd);
2190 GCC_check_connections ();
2196 * Handler for notifications of destroyed connections.
2198 * @param peer Message sender (neighbor).
2199 * @param msg Message itself.
2202 GCC_handle_destroy (struct CadetPeer *peer,
2203 const struct GNUNET_CADET_ConnectionDestroy *msg)
2205 struct CadetConnection *c;
2208 GCC_check_connections ();
2209 log_message (&msg->header, peer, &msg->cid);
2210 c = connection_get (&msg->cid);
2213 /* Probably already got the message from another path,
2214 * destroyed the tunnel and retransmitted to children.
2217 GNUNET_STATISTICS_update (stats,
2218 "# control on unknown connection",
2220 LOG (GNUNET_ERROR_TYPE_DEBUG,
2221 " connection unknown destroyed: previously destroyed?\n");
2222 GCC_check_connections ();
2226 fwd = is_fwd (c, peer);
2227 if (GNUNET_SYSERR == fwd)
2229 GNUNET_break_op (0);
2230 GCC_check_connections ();
2234 if (GNUNET_NO == GCC_is_terminal (c, fwd))
2236 (void) GCC_send_prebuilt_message (&msg->header, 0, 0, c, fwd,
2237 GNUNET_YES, NULL, NULL);
2239 else if (0 == c->pending_messages)
2241 LOG (GNUNET_ERROR_TYPE_DEBUG, " directly destroying connection!\n");
2243 GCC_check_connections ();
2249 GCT_remove_connection (c->t, c);
2252 GCC_check_connections ();
2258 * Handler for cadet network traffic hop-by-hop acks.
2260 * @param peer Message sender (neighbor).
2261 * @param msg Message itself.
2264 GCC_handle_ack (struct CadetPeer *peer,
2265 const struct GNUNET_CADET_ACK *msg)
2267 struct CadetConnection *c;
2268 struct CadetFlowControl *fc;
2272 GCC_check_connections ();
2273 log_message (&msg->header, peer, &msg->cid);
2274 c = connection_get (&msg->cid);
2277 GNUNET_STATISTICS_update (stats,
2278 "# ack on unknown connection",
2281 send_broken_unknown (&msg->cid,
2285 GCC_check_connections ();
2289 /* Is this a forward or backward ACK? */
2290 if (get_next_hop (c) == peer)
2295 else if (get_prev_hop (c) == peer)
2302 GNUNET_break_op (0);
2306 ack = ntohl (msg->ack);
2307 LOG (GNUNET_ERROR_TYPE_DEBUG, " %s ACK %u (was %u)\n",
2308 GC_f2s (fwd), ack, fc->last_ack_recv);
2309 if (GC_is_pid_bigger (ack, fc->last_ack_recv))
2310 fc->last_ack_recv = ack;
2312 /* Cancel polling if the ACK is big enough. */
2313 if (NULL != fc->poll_task &&
2314 GC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
2316 LOG (GNUNET_ERROR_TYPE_DEBUG, " Cancel poll\n");
2317 GNUNET_SCHEDULER_cancel (fc->poll_task);
2318 fc->poll_task = NULL;
2319 fc->poll_time = GNUNET_TIME_UNIT_SECONDS;
2322 GCC_check_connections ();
2327 * Handler for cadet network traffic hop-by-hop data counter polls.
2329 * @param peer Message sender (neighbor).
2330 * @param msg Message itself.
2333 GCC_handle_poll (struct CadetPeer *peer,
2334 const struct GNUNET_CADET_Poll *msg)
2336 struct CadetConnection *c;
2337 struct CadetFlowControl *fc;
2341 GCC_check_connections ();
2342 log_message (&msg->header, peer, &msg->cid);
2343 c = connection_get (&msg->cid);
2346 GNUNET_STATISTICS_update (stats, "# poll on unknown connection", 1,
2348 LOG (GNUNET_ERROR_TYPE_DEBUG,
2349 "POLL message on unknown connection %s!\n",
2350 GNUNET_h2s (GC_h2hc (&msg->cid)));
2351 send_broken_unknown (&msg->cid,
2355 GCC_check_connections ();
2359 /* Is this a forward or backward ACK?
2360 * Note: a poll should never be needed in a loopback case,
2361 * since there is no possiblility of packet loss there, so
2362 * this way of discerining FWD/BCK should not be a problem.
2364 if (get_next_hop (c) == peer)
2366 LOG (GNUNET_ERROR_TYPE_DEBUG, " FWD FC\n");
2369 else if (get_prev_hop (c) == peer)
2371 LOG (GNUNET_ERROR_TYPE_DEBUG, " BCK FC\n");
2376 GNUNET_break_op (0);
2380 pid = ntohl (msg->pid);
2381 LOG (GNUNET_ERROR_TYPE_DEBUG, " PID %u, OLD %u\n", pid, fc->last_pid_recv);
2382 fc->last_pid_recv = pid;
2383 fwd = fc == &c->bck_fc;
2384 GCC_send_ack (c, fwd, GNUNET_YES);
2385 GCC_check_connections ();
2390 * Check the message against internal state and test if it goes FWD or BCK.
2392 * Updates the PID, state and timeout values for the connection.
2394 * @param message Message to check. It must belong to an existing connection.
2395 * @param cid Connection ID (even if @a c is NULL, the ID is still needed).
2396 * @param c Connection this message should belong. If NULL, check fails.
2397 * @param sender Neighbor that sent the message.
2399 * @return #GNUNET_YES if the message goes FWD.
2400 * #GNUNET_NO if it goes BCK.
2401 * #GNUNET_SYSERR if there is an error (unauthorized sender, ...).
2404 check_message (const struct GNUNET_MessageHeader *message,
2405 const struct GNUNET_CADET_Hash* cid,
2406 struct CadetConnection *c,
2407 struct CadetPeer *sender,
2410 struct CadetFlowControl *fc;
2411 struct CadetPeer *hop;
2415 /* Check connection */
2418 GNUNET_STATISTICS_update (stats,
2419 "# unknown connection",
2421 LOG (GNUNET_ERROR_TYPE_DEBUG,
2422 "%s on unknown connection %s\n",
2423 GC_m2s (ntohs (message->type)),
2424 GNUNET_h2s (GC_h2hc (cid)));
2425 send_broken_unknown (cid,
2429 return GNUNET_SYSERR;
2432 /* Check if origin is as expected */
2433 hop = get_prev_hop (c);
2440 hop = get_next_hop (c);
2441 GNUNET_break (hop == c->next_peer);
2448 /* Unexpected peer sending traffic on a connection. */
2449 GNUNET_break_op (0);
2450 return GNUNET_SYSERR;
2454 /* Check PID for payload messages */
2455 type = ntohs (message->type);
2456 if (GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED == type)
2458 fc = fwd ? &c->bck_fc : &c->fwd_fc;
2459 LOG (GNUNET_ERROR_TYPE_DEBUG, " PID %u (expected %u - %u)\n",
2460 pid, fc->last_pid_recv + 1, fc->last_ack_sent);
2461 if (GC_is_pid_bigger (pid, fc->last_ack_sent))
2463 GNUNET_break_op (0);
2464 GNUNET_STATISTICS_update (stats, "# unsolicited message", 1, GNUNET_NO);
2465 LOG (GNUNET_ERROR_TYPE_WARNING, "Received PID %u, (prev %u), ACK %u\n",
2466 pid, fc->last_pid_recv, fc->last_ack_sent);
2467 return GNUNET_SYSERR;
2469 if (GC_is_pid_bigger (pid, fc->last_pid_recv))
2473 delta = pid - fc->last_pid_recv;
2474 fc->last_pid_recv = pid;
2475 fc->recv_bitmap <<= delta;
2476 fc->recv_bitmap |= 1;
2480 GNUNET_STATISTICS_update (stats, "# out of order PID", 1, GNUNET_NO);
2481 if (GNUNET_NO == is_ooo_ok (fc->last_pid_recv, pid, fc->recv_bitmap))
2483 LOG (GNUNET_ERROR_TYPE_WARNING, "PID %u unexpected (%u+), dropping!\n",
2484 pid, fc->last_pid_recv - 31);
2485 return GNUNET_SYSERR;
2487 fc->recv_bitmap |= get_recv_bitmask (fc->last_pid_recv, pid);
2491 /* Count as connection confirmation. */
2492 if (CADET_CONNECTION_SENT == c->state || CADET_CONNECTION_ACK == c->state)
2494 connection_change_state (c, CADET_CONNECTION_READY);
2497 if (CADET_TUNNEL_WAITING == GCT_get_cstate (c->t))
2498 GCT_change_cstate (c->t, CADET_TUNNEL_READY);
2501 connection_reset_timeout (c, fwd);
2508 * Handler for key exchange traffic (Axolotl KX).
2510 * @param peer Message sender (neighbor).
2511 * @param msg Message itself.
2514 GCC_handle_kx (struct CadetPeer *peer,
2515 const struct GNUNET_CADET_KX *msg)
2517 const struct GNUNET_CADET_Hash* cid;
2518 struct CadetConnection *c;
2521 GCC_check_connections ();
2523 log_message (&msg->header, peer, cid);
2525 c = connection_get (cid);
2526 fwd = check_message (&msg->header,
2532 /* If something went wrong, discard message. */
2533 if (GNUNET_SYSERR == fwd)
2535 GNUNET_break_op (0);
2536 GCC_check_connections ();
2540 /* Is this message for us? */
2541 if (GCC_is_terminal (c, fwd))
2543 LOG (GNUNET_ERROR_TYPE_DEBUG, " message for us!\n");
2544 GNUNET_STATISTICS_update (stats, "# received KX", 1, GNUNET_NO);
2550 GCT_handle_kx (c->t, msg);
2551 GCC_check_connections ();
2555 /* Message not for us: forward to next hop */
2556 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2557 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
2558 (void) GCC_send_prebuilt_message (&msg->header, 0, 0, c, fwd,
2559 GNUNET_NO, NULL, NULL);
2560 GCC_check_connections ();
2565 * Handler for encrypted cadet network traffic (channel mgmt, data).
2567 * @param peer Message sender (neighbor).
2568 * @param msg Message itself.
2571 GCC_handle_encrypted (struct CadetPeer *peer,
2572 const struct GNUNET_CADET_Encrypted *msg)
2574 const struct GNUNET_CADET_Hash* cid;
2575 struct CadetConnection *c;
2579 GCC_check_connections ();
2581 pid = ntohl (msg->pid);
2582 log_message (&msg->header, peer, cid);
2584 c = connection_get (cid);
2585 fwd = check_message (&msg->header,
2591 /* If something went wrong, discard message. */
2592 if (GNUNET_SYSERR == fwd)
2594 GNUNET_break_op (0);
2595 GCC_check_connections ();
2599 /* Is this message for us? */
2600 if (GCC_is_terminal (c, fwd))
2602 GNUNET_STATISTICS_update (stats, "# received encrypted", 1, GNUNET_NO);
2606 GNUNET_break (GNUNET_NO != c->destroy);
2609 GCT_handle_encrypted (c->t, msg);
2610 GCC_send_ack (c, fwd, GNUNET_NO);
2611 GCC_check_connections ();
2615 /* Message not for us: forward to next hop */
2616 LOG (GNUNET_ERROR_TYPE_DEBUG, " not for us, retransmitting...\n");
2617 GNUNET_STATISTICS_update (stats, "# messages forwarded", 1, GNUNET_NO);
2618 (void) GCC_send_prebuilt_message (&msg->header, 0, 0, c, fwd,
2619 GNUNET_NO, NULL, NULL);
2620 GCC_check_connections ();
2625 * Initialize the connections subsystem
2627 * @param c Configuration handle.
2630 GCC_init (const struct GNUNET_CONFIGURATION_Handle *c)
2632 LOG (GNUNET_ERROR_TYPE_DEBUG, "init\n");
2634 GNUNET_CONFIGURATION_get_value_number (c, "CADET", "MAX_MSGS_QUEUE",
2637 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2638 "CADET", "MAX_MSGS_QUEUE", "MISSING");
2639 GNUNET_SCHEDULER_shutdown ();
2644 GNUNET_CONFIGURATION_get_value_number (c, "CADET", "MAX_CONNECTIONS",
2647 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2648 "CADET", "MAX_CONNECTIONS", "MISSING");
2649 GNUNET_SCHEDULER_shutdown ();
2654 GNUNET_CONFIGURATION_get_value_time (c, "CADET", "REFRESH_CONNECTION_TIME",
2655 &refresh_connection_time))
2657 GNUNET_log_config_invalid (GNUNET_ERROR_TYPE_ERROR,
2658 "CADET", "REFRESH_CONNECTION_TIME", "MISSING");
2659 GNUNET_SCHEDULER_shutdown ();
2662 create_connection_time = GNUNET_TIME_relative_min (GNUNET_TIME_UNIT_SECONDS,
2663 refresh_connection_time);
2664 connections = GNUNET_CONTAINER_multihashmap_create (1024, GNUNET_NO);
2669 * Destroy each connection on shutdown.
2671 * @param cls Closure (unused).
2672 * @param key Current key code (CID, unused).
2673 * @param value Value in the hash map (`struct CadetConnection`)
2675 * @return #GNUNET_YES, because we should continue to iterate
2678 shutdown_iterator (void *cls,
2679 const struct GNUNET_HashCode *key,
2682 struct CadetConnection *c = value;
2684 c->state = CADET_CONNECTION_DESTROYED;
2691 * Shut down the connections subsystem.
2696 LOG (GNUNET_ERROR_TYPE_DEBUG, "Shutting down connections\n");
2697 GCC_check_connections ();
2698 GNUNET_CONTAINER_multihashmap_iterate (connections,
2701 GNUNET_CONTAINER_multihashmap_destroy (connections);
2707 * Create a connection.
2709 * @param cid Connection ID (either created locally or imposed remotely).
2710 * @param t Tunnel this connection belongs to (or NULL for transit connections);
2711 * @param path Path this connection has to use (copy is made).
2712 * @param own_pos Own position in the @c path path.
2714 * @return Newly created connection.
2715 * NULL in case of error: own id not in path, wrong neighbors, ...
2717 struct CadetConnection *
2718 GCC_new (const struct GNUNET_CADET_Hash *cid,
2719 struct CadetTunnel *t,
2720 struct CadetPeerPath *path,
2721 unsigned int own_pos)
2723 struct CadetConnection *c;
2724 struct CadetPeerPath *cpath;
2726 GCC_check_connections ();
2727 cpath = path_duplicate (path);
2728 GNUNET_assert (NULL != cpath);
2729 c = GNUNET_new (struct CadetConnection);
2731 GNUNET_assert (GNUNET_OK ==
2732 GNUNET_CONTAINER_multihashmap_put (connections,
2734 GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_ONLY));
2735 fc_init (&c->fwd_fc);
2736 fc_init (&c->bck_fc);
2741 GNUNET_assert (own_pos <= cpath->length - 1);
2742 c->own_pos = own_pos;
2745 if (GNUNET_OK != register_neighbors (c))
2749 /* We were the origin of this request, this means we have invalid
2750 * info about the paths to reach the destination. We must invalidate
2751 * the *original* path to avoid trying it again in the next minute.
2753 if (2 < path->length)
2754 path_invalidate (path);
2758 GCT_debug(t, GNUNET_ERROR_TYPE_WARNING);
2762 path_destroy (c->path);
2767 LOG (GNUNET_ERROR_TYPE_INFO, "New connection %s\n", GCC_2s (c));
2768 GCC_check_connections ();
2774 * Connection is no longer needed: destroy it.
2776 * Cancels all pending traffic (including possible DESTROY messages), all
2777 * maintenance tasks and removes the connection from neighbor peers and tunnel.
2779 * @param c Connection to destroy.
2782 GCC_destroy (struct CadetConnection *c)
2784 GCC_check_connections ();
2791 if (2 == c->destroy) /* cancel queues -> GCP_queue_cancel -> q_destroy -> */
2792 return; /* -> message_sent -> GCC_destroy. Don't loop. */
2795 LOG (GNUNET_ERROR_TYPE_DEBUG,
2796 "destroying connection %s\n",
2798 LOG (GNUNET_ERROR_TYPE_DEBUG,
2799 " fc's f: %p, b: %p\n",
2800 &c->fwd_fc, &c->bck_fc);
2801 LOG (GNUNET_ERROR_TYPE_DEBUG,
2802 " fc tasks f: %u, b: %u\n",
2803 c->fwd_fc.poll_task,
2804 c->bck_fc.poll_task);
2806 /* Cancel all traffic */
2807 if (NULL != c->path)
2809 connection_cancel_queues (c, GNUNET_YES);
2810 connection_cancel_queues (c, GNUNET_NO);
2811 if (NULL != c->maintenance_q)
2813 GCP_send_cancel (c->maintenance_q);
2814 c->maintenance_q = NULL;
2817 unregister_neighbors (c);
2818 path_destroy (c->path);
2821 /* Delete from tunnel */
2823 GCT_remove_connection (c->t, c);
2825 if (NULL != c->check_duplicates_task)
2826 GNUNET_SCHEDULER_cancel (c->check_duplicates_task);
2827 if (NULL != c->fwd_maintenance_task)
2828 GNUNET_SCHEDULER_cancel (c->fwd_maintenance_task);
2829 if (NULL != c->bck_maintenance_task)
2830 GNUNET_SCHEDULER_cancel (c->bck_maintenance_task);
2832 if (GNUNET_NO == c->was_removed)
2834 GNUNET_break (GNUNET_YES ==
2835 GNUNET_CONTAINER_multihashmap_remove (connections,
2839 GNUNET_STATISTICS_update (stats,
2844 GCC_check_connections ();
2849 * Get the connection ID.
2851 * @param c Connection to get the ID from.
2853 * @return ID of the connection.
2855 const struct GNUNET_CADET_Hash *
2856 GCC_get_id (const struct CadetConnection *c)
2863 * Get the connection ID.
2865 * @param c Connection to get the ID from.
2867 * @return ID of the connection.
2869 const struct GNUNET_HashCode *
2870 GCC_get_h (const struct CadetConnection *c)
2872 return GC_h2hc (&c->id);
2877 * Get the connection path.
2879 * @param c Connection to get the path from.
2881 * @return path used by the connection.
2883 const struct CadetPeerPath *
2884 GCC_get_path (const struct CadetConnection *c)
2886 if (GNUNET_NO == c->destroy)
2893 * Get the connection state.
2895 * @param c Connection to get the state from.
2897 * @return state of the connection.
2899 enum CadetConnectionState
2900 GCC_get_state (const struct CadetConnection *c)
2906 * Get the connection tunnel.
2908 * @param c Connection to get the tunnel from.
2910 * @return tunnel of the connection.
2912 struct CadetTunnel *
2913 GCC_get_tunnel (const struct CadetConnection *c)
2920 * Get free buffer space in a connection.
2922 * @param c Connection.
2923 * @param fwd Is query about FWD traffic?
2925 * @return Free buffer space [0 - max_msgs_queue/max_connections]
2928 GCC_get_buffer (struct CadetConnection *c, int fwd)
2930 struct CadetFlowControl *fc;
2932 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2934 LOG (GNUNET_ERROR_TYPE_DEBUG, " Get %s buffer on %s: %u - %u\n",
2935 GC_f2s (fwd), GCC_2s (c), fc->queue_max, fc->queue_n);
2936 GCC_debug (c, GNUNET_ERROR_TYPE_DEBUG);
2938 return (fc->queue_max - fc->queue_n);
2943 * Get how many messages have we allowed to send to us from a direction.
2945 * @param c Connection.
2946 * @param fwd Are we asking about traffic from FWD (BCK messages)?
2948 * @return last_ack_sent - last_pid_recv
2951 GCC_get_allowed (struct CadetConnection *c, int fwd)
2953 struct CadetFlowControl *fc;
2955 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2956 if (CADET_CONNECTION_READY != c->state
2957 || GC_is_pid_bigger (fc->last_pid_recv, fc->last_ack_sent))
2961 return (fc->last_ack_sent - fc->last_pid_recv);
2966 * Get messages queued in a connection.
2968 * @param c Connection.
2969 * @param fwd Is query about FWD traffic?
2971 * @return Number of messages queued.
2974 GCC_get_qn (struct CadetConnection *c, int fwd)
2976 struct CadetFlowControl *fc;
2978 fc = fwd ? &c->fwd_fc : &c->bck_fc;
2985 * Get next PID to use.
2987 * @param c Connection.
2988 * @param fwd Is query about FWD traffic?
2990 * @return Next PID to use.
2993 GCC_get_pid (struct CadetConnection *c, int fwd)
2995 struct CadetFlowControl *fc;
2998 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3006 * Allow the connection to advertise a buffer of the given size.
3008 * The connection will send an @c fwd ACK message (so: in direction !fwd)
3009 * allowing up to last_pid_recv + buffer.
3011 * @param c Connection.
3012 * @param buffer How many more messages the connection can accept.
3013 * @param fwd Is this about FWD traffic? (The ack will go dest->root).
3016 GCC_allow (struct CadetConnection *c, unsigned int buffer, int fwd)
3018 LOG (GNUNET_ERROR_TYPE_DEBUG, " allowing %s %u messages %s\n",
3019 GCC_2s (c), buffer, GC_f2s (fwd));
3020 send_ack (c, buffer, fwd, GNUNET_NO);
3025 * Notify other peers on a connection of a broken link. Mark connections
3026 * to destroy after all traffic has been sent.
3028 * @param c Connection on which there has been a disconnection.
3029 * @param peer Peer that disconnected.
3032 GCC_neighbor_disconnected (struct CadetConnection *c, struct CadetPeer *peer)
3034 struct CadetFlowControl *fc;
3038 GCC_check_connections ();
3039 strncpy (peer_name, GCP_2s (peer), 16);
3040 peer_name[15] = '\0';
3041 LOG (GNUNET_ERROR_TYPE_DEBUG,
3042 "shutting down %s, %s disconnected\n",
3043 GCC_2s (c), peer_name);
3045 invalidate_paths (c, peer);
3047 fwd = is_fwd (c, peer);
3048 if (GNUNET_SYSERR == fwd)
3053 if ( (GNUNET_YES == GCC_is_terminal (c, fwd)) ||
3054 (GNUNET_NO != c->destroy) )
3056 /* Local shutdown, or other peer already down (hence 'c->destroy');
3057 so there is no one to notify about this, just clean up. */
3059 GCC_check_connections ();
3062 /* Mark FlowControl towards the peer as unavaliable. */
3063 fc = fwd ? &c->bck_fc : &c->fwd_fc;
3066 send_broken (c, &my_full_id, GCP_get_id (peer), fwd);
3068 /* Connection will have at least one pending message
3069 * (the one we just scheduled), so delay destruction
3070 * and remove from map so we don't use accidentally. */
3072 GNUNET_assert (GNUNET_NO == c->was_removed);
3073 c->was_removed = GNUNET_YES;
3074 GNUNET_break (GNUNET_YES ==
3075 GNUNET_CONTAINER_multihashmap_remove (connections,
3078 /* Cancel queue in the direction that just died. */
3079 connection_cancel_queues (c, ! fwd);
3080 GCC_stop_poll (c, ! fwd);
3081 unregister_neighbors (c);
3082 GCC_check_connections ();
3087 * Is this peer the first one on the connection?
3089 * @param c Connection.
3090 * @param fwd Is this about fwd traffic?
3092 * @return #GNUNET_YES if origin, #GNUNET_NO if relay/terminal.
3095 GCC_is_origin (struct CadetConnection *c, int fwd)
3097 if (!fwd && c->path->length - 1 == c->own_pos )
3099 if (fwd && 0 == c->own_pos)
3106 * Is this peer the last one on the connection?
3108 * @param c Connection.
3109 * @param fwd Is this about fwd traffic?
3110 * Note that the ROOT is the terminal for BCK traffic!
3112 * @return #GNUNET_YES if terminal, #GNUNET_NO if relay/origin.
3115 GCC_is_terminal (struct CadetConnection *c, int fwd)
3117 return GCC_is_origin (c, ! fwd);
3122 * See if we are allowed to send by the next hop in the given direction.
3124 * @param c Connection.
3125 * @param fwd Is this about fwd traffic?
3127 * @return #GNUNET_YES in case it's OK to send.
3130 GCC_is_sendable (struct CadetConnection *c, int fwd)
3132 struct CadetFlowControl *fc;
3134 LOG (GNUNET_ERROR_TYPE_DEBUG,
3135 " checking sendability of %s traffic on %s\n",
3136 GC_f2s (fwd), GCC_2s (c));
3142 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3143 LOG (GNUNET_ERROR_TYPE_DEBUG,
3144 " last ack recv: %u, last pid sent: %u\n",
3145 fc->last_ack_recv, fc->last_pid_sent);
3146 if (GC_is_pid_bigger (fc->last_ack_recv, fc->last_pid_sent))
3148 LOG (GNUNET_ERROR_TYPE_DEBUG, " sendable\n");
3151 LOG (GNUNET_ERROR_TYPE_DEBUG, " not sendable\n");
3157 * Check if this connection is a direct one (never trim a direct connection).
3159 * @param c Connection.
3161 * @return #GNUNET_YES in case it's a direct connection, #GNUNET_NO otherwise.
3164 GCC_is_direct (struct CadetConnection *c)
3166 return (c->path->length == 2) ? GNUNET_YES : GNUNET_NO;
3171 * Sends a completely built message on a connection, properly registering
3172 * all used resources.
3174 * @param message Message to send.
3175 * @param payload_type Type of payload, in case the message is encrypted.
3176 * 0 for restransmissions (when type is no longer known)
3177 * UINT16_MAX when not applicable.
3178 * @param payload_id ID of the payload (PID, ACK, ...).
3179 * @param c Connection on which this message is transmitted.
3180 * @param fwd Is this a fwd message?
3181 * @param force Force the connection to accept the message (buffer overfill).
3182 * @param cont Continuation called once message is sent. Can be NULL.
3183 * @param cont_cls Closure for @c cont.
3185 * @return Handle to cancel the message before it's sent.
3187 * Invalid on @c cont call.
3189 struct CadetConnectionQueue *
3190 GCC_send_prebuilt_message (const struct GNUNET_MessageHeader *message,
3191 uint16_t payload_type, uint32_t payload_id,
3192 struct CadetConnection *c, int fwd, int force,
3193 GCC_sent cont, void *cont_cls)
3195 struct CadetFlowControl *fc;
3196 struct CadetConnectionQueue *q;
3200 size = ntohs (message->size);
3201 type = ntohs (message->type);
3203 GCC_check_connections ();
3204 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3205 if (0 == fc->queue_max)
3211 LOG (GNUNET_ERROR_TYPE_INFO,
3212 "--> %s (%s %4u) on conn %s (%p) %s [%5u]\n",
3213 GC_m2s (type), GC_m2s (payload_type), payload_id, GCC_2s (c), c,
3217 case GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED:
3218 LOG (GNUNET_ERROR_TYPE_DEBUG, " Q_N+ %p %u, PIDsnt: %u, ACKrcv: %u\n",
3219 fc, fc->queue_n, fc->last_pid_sent, fc->last_ack_recv);
3220 if (GNUNET_NO == force)
3226 case GNUNET_MESSAGE_TYPE_CADET_KX:
3227 /* nothing to do here */
3230 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE:
3231 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_ACK:
3232 /* Should've only be used for restransmissions. */
3233 GNUNET_break (0 == payload_type);
3236 case GNUNET_MESSAGE_TYPE_CADET_ACK:
3237 case GNUNET_MESSAGE_TYPE_CADET_POLL:
3238 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY:
3239 case GNUNET_MESSAGE_TYPE_CADET_CONNECTION_BROKEN:
3240 GNUNET_assert (GNUNET_YES == force);
3248 if (fc->queue_n > fc->queue_max && GNUNET_NO == force)
3250 GNUNET_STATISTICS_update (stats, "# messages dropped (buffer full)",
3253 LOG (GNUNET_ERROR_TYPE_DEBUG, "queue full: %u/%u\n",
3254 fc->queue_n, fc->queue_max);
3255 if (GNUNET_MESSAGE_TYPE_CADET_ENCRYPTED == type)
3259 return NULL; /* Drop this message */
3262 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %s %u\n",
3263 GCC_2s (c), c->pending_messages);
3264 c->pending_messages++;
3266 q = GNUNET_new (struct CadetConnectionQueue);
3268 q->cont_cls = cont_cls;
3270 GNUNET_CONTAINER_DLL_insert (fc->q_head, fc->q_tail, q);
3271 q->peer_q = GCP_send (get_hop (c, fwd), message,
3272 payload_type, payload_id,
3274 &conn_message_sent, q);
3275 if (NULL == q->peer_q)
3277 LOG (GNUNET_ERROR_TYPE_DEBUG, "dropping msg on %s, NULL q\n", GCC_2s (c));
3278 GNUNET_CONTAINER_DLL_remove (fc->q_head, fc->q_tail, q);
3280 GCC_check_connections ();
3283 GCC_check_connections ();
3289 * Cancel a previously sent message while it's in the queue.
3291 * ONLY can be called before the continuation given to the send function
3292 * is called. Once the continuation is called, the message is no longer in the
3295 * @param q Handle to the queue.
3298 GCC_cancel (struct CadetConnectionQueue *q)
3300 LOG (GNUNET_ERROR_TYPE_DEBUG, "! GCC cancel message\n");
3302 /* send_cancel calls message_sent, which calls q->cont and frees q */
3303 GCP_send_cancel (q->peer_q);
3304 GCC_check_connections ();
3309 * Sends a CREATE CONNECTION message for a path to a peer.
3310 * Changes the connection and tunnel states if necessary.
3312 * @param c Connection to create.
3315 GCC_send_create (struct CadetConnection *c)
3317 enum CadetTunnelCState state;
3320 GCC_check_connections ();
3321 size = sizeof (struct GNUNET_CADET_ConnectionCreate);
3322 size += c->path->length * sizeof (struct GNUNET_PeerIdentity);
3324 /* Allocate message on the stack */
3325 unsigned char cbuf[size];
3326 struct GNUNET_CADET_ConnectionCreate *msg;
3327 struct GNUNET_PeerIdentity *peers;
3329 msg = (struct GNUNET_CADET_ConnectionCreate *) cbuf;
3330 msg->header.size = htons (size);
3331 msg->header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE);
3332 msg->reserved = htonl (0);
3333 msg->cid = *GCC_get_id (c);
3334 peers = (struct GNUNET_PeerIdentity *) &msg[1];
3335 for (int i = 0; i < c->path->length; i++)
3337 GNUNET_PEER_resolve (c->path->peers[i], peers++);
3339 GNUNET_assert (NULL == c->maintenance_q);
3340 c->maintenance_q = GCP_send (get_next_hop (c),
3342 GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE, 0,
3344 &conn_message_sent, NULL);
3347 LOG (GNUNET_ERROR_TYPE_INFO, "==> %s %19s on conn %s (%p) FWD [%5u]\n",
3348 GC_m2s (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_CREATE), "",
3349 GCC_2s (c), c, size);
3350 LOG (GNUNET_ERROR_TYPE_DEBUG, " C_P+ %p %u (create)\n",
3351 c, c->pending_messages);
3352 c->pending_messages++;
3354 state = GCT_get_cstate (c->t);
3355 if (CADET_TUNNEL_SEARCHING == state || CADET_TUNNEL_NEW == state)
3356 GCT_change_cstate (c->t, CADET_TUNNEL_WAITING);
3357 if (CADET_CONNECTION_NEW == c->state)
3358 connection_change_state (c, CADET_CONNECTION_SENT);
3359 GCC_check_connections ();
3364 * Send an ACK on the appropriate connection/channel, depending on
3365 * the direction and the position of the peer.
3367 * @param c Which connection to send the hop-by-hop ACK.
3368 * @param fwd Is this a fwd ACK? (will go dest->root).
3369 * @param force Send the ACK even if suboptimal (e.g. requested by POLL).
3372 GCC_send_ack (struct CadetConnection *c, int fwd, int force)
3374 unsigned int buffer;
3376 GCC_check_connections ();
3377 LOG (GNUNET_ERROR_TYPE_DEBUG, "GCC send %s ACK on %s\n",
3378 GC_f2s (fwd), GCC_2s (c));
3386 if (GNUNET_NO != c->destroy)
3388 LOG (GNUNET_ERROR_TYPE_DEBUG, " being destroyed, why bother...\n");
3389 GCC_check_connections ();
3393 /* Get available buffer space */
3394 if (GCC_is_terminal (c, fwd))
3396 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from all channels\n");
3397 buffer = GCT_get_channels_buffer (c->t);
3401 LOG (GNUNET_ERROR_TYPE_DEBUG, " getting from one connection\n");
3402 buffer = GCC_get_buffer (c, fwd);
3404 LOG (GNUNET_ERROR_TYPE_DEBUG, " buffer available: %u\n", buffer);
3405 if (0 == buffer && GNUNET_NO == force)
3407 GCC_check_connections ();
3411 /* Send available buffer space */
3412 if (GNUNET_YES == GCC_is_origin (c, fwd))
3414 GNUNET_assert (NULL != c->t);
3415 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on channels...\n");
3416 GCT_unchoke_channels (c->t);
3420 LOG (GNUNET_ERROR_TYPE_DEBUG, " sending on connection\n");
3421 send_ack (c, buffer, fwd, force);
3423 GCC_check_connections ();
3428 * Send a message to all peers in this connection that the connection
3429 * is no longer valid.
3431 * If some peer should not receive the message, it should be zero'ed out
3432 * before calling this function.
3434 * @param c The connection whose peers to notify.
3437 GCC_send_destroy (struct CadetConnection *c)
3439 struct GNUNET_CADET_ConnectionDestroy msg;
3441 if (GNUNET_YES == c->destroy)
3443 GCC_check_connections ();
3444 msg.header.size = htons (sizeof (msg));
3445 msg.header.type = htons (GNUNET_MESSAGE_TYPE_CADET_CONNECTION_DESTROY);
3447 msg.reserved = htonl (0);
3448 LOG (GNUNET_ERROR_TYPE_DEBUG,
3449 " sending connection destroy for connection %s\n",
3452 if (GNUNET_NO == GCC_is_terminal (c, GNUNET_YES))
3453 (void) GCC_send_prebuilt_message (&msg.header, UINT16_MAX, 0, c,
3454 GNUNET_YES, GNUNET_YES, NULL, NULL);
3455 if (GNUNET_NO == GCC_is_terminal (c, GNUNET_NO))
3456 (void) GCC_send_prebuilt_message (&msg.header, UINT16_MAX, 0, c,
3457 GNUNET_NO, GNUNET_YES, NULL, NULL);
3459 GCC_check_connections ();
3464 * @brief Start a polling timer for the connection.
3466 * When a neighbor does not accept more traffic on the connection it could be
3467 * caused by a simple congestion or by a lost ACK. Polling enables to check
3468 * for the lastest ACK status for a connection.
3470 * @param c Connection.
3471 * @param fwd Should we poll in the FWD direction?
3474 GCC_start_poll (struct CadetConnection *c, int fwd)
3476 struct CadetFlowControl *fc;
3478 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3479 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL %s requested\n",
3481 if (NULL != fc->poll_task || NULL != fc->poll_msg)
3483 LOG (GNUNET_ERROR_TYPE_DEBUG, " POLL already in progress (t: %p, m: %p)\n",
3484 fc->poll_task, fc->poll_msg);
3487 if (0 == fc->queue_max)
3489 /* Should not be needed, traffic should've been cancelled. */
3491 LOG (GNUNET_ERROR_TYPE_DEBUG, " POLL not possible, peer disconnected\n");
3494 LOG (GNUNET_ERROR_TYPE_DEBUG, "POLL started on request\n");
3495 fc->poll_task = GNUNET_SCHEDULER_add_delayed (fc->poll_time, &send_poll, fc);
3500 * @brief Stop polling a connection for ACKs.
3502 * Once we have enough ACKs for future traffic, polls are no longer necessary.
3504 * @param c Connection.
3505 * @param fwd Should we stop the poll in the FWD direction?
3508 GCC_stop_poll (struct CadetConnection *c, int fwd)
3510 struct CadetFlowControl *fc;
3512 fc = fwd ? &c->fwd_fc : &c->bck_fc;
3513 if (NULL != fc->poll_task)
3515 GNUNET_SCHEDULER_cancel (fc->poll_task);
3516 fc->poll_task = NULL;
3518 if (NULL != fc->poll_msg)
3520 GCC_cancel (fc->poll_msg);
3521 fc->poll_msg = NULL;
3527 * Get a (static) string for a connection.
3529 * @param c Connection.
3532 GCC_2s (const struct CadetConnection *c)
3539 static char buf[128];
3541 SPRINTF (buf, "%s (->%s)",
3542 GNUNET_h2s (GC_h2hc (GCC_get_id (c))), GCT_2s (c->t));
3545 return GNUNET_h2s (GC_h2hc (&c->id));
3550 * Log all possible info about the connection state.
3552 * @param c Connection to debug.
3553 * @param level Debug level to use.
3556 GCC_debug (const struct CadetConnection *c, enum GNUNET_ErrorType level)
3561 do_log = GNUNET_get_log_call_status (level & (~GNUNET_ERROR_TYPE_BULK),
3563 __FILE__, __FUNCTION__, __LINE__);
3569 LOG2 (level, "CCC DEBUG NULL CONNECTION\n");
3573 LOG2 (level, "CCC DEBUG CONNECTION %s\n", GCC_2s (c));
3574 s = path_2s (c->path);
3575 LOG2 (level, "CCC path %s, own pos: %u\n", s, c->own_pos);
3577 LOG2 (level, "CCC state: %s, destroy: %u\n",
3578 GCC_state2s (c->state), c->destroy);
3579 LOG2 (level, "CCC pending messages: %u\n", c->pending_messages);
3580 if (NULL != c->perf)
3581 LOG2 (level, "CCC us/byte: %f\n", c->perf->avg);
3583 LOG2 (level, "CCC FWD flow control:\n");
3584 LOG2 (level, "CCC queue: %u/%u\n", c->fwd_fc.queue_n, c->fwd_fc.queue_max);
3585 LOG2 (level, "CCC last PID sent: %5u, recv: %5u\n",
3586 c->fwd_fc.last_pid_sent, c->fwd_fc.last_pid_recv);
3587 LOG2 (level, "CCC last ACK sent: %5u, recv: %5u\n",
3588 c->fwd_fc.last_ack_sent, c->fwd_fc.last_ack_recv);
3589 LOG2 (level, "CCC recv PID bitmap: %X\n", c->fwd_fc.recv_bitmap);
3590 LOG2 (level, "CCC poll: task %d, msg %p, msg_ack %p)\n",
3591 c->fwd_fc.poll_task, c->fwd_fc.poll_msg, c->fwd_fc.ack_msg);
3593 LOG2 (level, "CCC BCK flow control:\n");
3594 LOG2 (level, "CCC queue: %u/%u\n", c->bck_fc.queue_n, c->bck_fc.queue_max);
3595 LOG2 (level, "CCC last PID sent: %5u, recv: %5u\n",
3596 c->bck_fc.last_pid_sent, c->bck_fc.last_pid_recv);
3597 LOG2 (level, "CCC last ACK sent: %5u, recv: %5u\n",
3598 c->bck_fc.last_ack_sent, c->bck_fc.last_ack_recv);
3599 LOG2 (level, "CCC recv PID bitmap: %X\n", c->bck_fc.recv_bitmap);
3600 LOG2 (level, "CCC poll: task %d, msg %p, msg_ack %p)\n",
3601 c->bck_fc.poll_task, c->bck_fc.poll_msg, c->bck_fc.ack_msg);
3603 LOG2 (level, "CCC DEBUG CONNECTION END\n");